The US Court of Appeals for the Fourth Circuit ruled Tuesday that a North Carolina school’s dress code requiring females to wear skirts violates the 14th Amendment’s Equal Protection Clause.

The Charter Day School required all female students to wear skirts, noting that “girls are ‘fragile vessels’ deserving of ‘gentle’ treatment by boys.” Male students were required to wear shorts or pants. All students were required to wear a unisex polo shirt. Failure to comply with the dress code resulted in disciplinary measures, including parental notification, removal from class, and even expulsion.

Several mothers of female students sued the school and argued the dress code was a “sex-based classification rooted in gender stereotypes.” They asserted that the dress code made female students feel like they were more delicate than boys, were not worth as much as boys, and should be less active than boys. Additionally, girls avoided numerous physical activities in school, like climbing, using the swings, and playing soccer due to the skirt requirement.

The charter school responded by claiming they emphasized “traditional values” and implemented the dress code to instill discipline and keep order.

The Fourth Circuit decided that the dress code was discriminatory and treated females unequally. The school’s interest in preserving traditional values was not sufficient to withstand judicial scrutiny. The court concluded that if the school wishes to keep its “traditional” dress code, then it cannot operate as a charter school.